Apparatus for automatically drawing maps and plans from two terrestrial or aerial photographs



July 10, 1928.

G. J. POIVILLIERS APPARATUS FOR AUTOMATICALLY DRAWING MAPSv AND PLANSFROM TWO TERRESTIAL OR AERIAL PHOTOGRAPHS Filed April 16, 1923 6Sheets-Sheet 1 July 10, 1928. 1,676,708

G. J. POIVILLIERS APPARATUS FOR AUTOMATICALLY DRAWING MAPS AND PLANS"FROM TWO TERRESTIAL OR AERIAL PHOTOGRAPHS Filed April 16, 1925 6Sheets-Sheet W WMHW July 10, 1928. 1,676,708

a. J. POIVILLIERS APPARATUS FOR AUTOMATICALLY DRAWING MAPS AND PLANSFROM TWO TERRESTIAL OR AERIAL PHOTOGRAPHS FiledApril 16, 1923 6Sheets-Sheet 3 'IM TO, 192s.

1,676,708 G. J. POIVILLIERS APPARATUS FOR AUTOMATICALLY DRAWING MAPS ANDPLANS mom TWO TERRESTIAL'OR AERIAL PHOTOGRAPHS Filed Aprillfi, 1925 6Sheets-Sheet 4 July 10, 1928. 4 1,676,708

G. J. POIVILLIERS APPARATUS FOR AUTOMATICALLY DRAWING MAPS AND PLANSFROM I TWO TERRESTIAL OR AERIAL PHOTOGRAPHS Filed April 16, 1923 -6Sheets-Sheet 5 Hg. Z

July 10, 1928. 1,676,708

G. J. POIVILLlE-RS APPARATUS FOR AUTOMATICALLY DRAWING MAPS AND PLANSFROM TWO TERRESTIAL OR AERIAL PHOTOGRAPHS Filed April 16, 1923 6Sheets-Sheet 6 E El 9 Patented Jul 10, 1928.

PATENT OFFICE. I

' UNITED STATES GEORGES JEAN POIVILLIERS, OF PARIS, FRANCE.

APPARATUS FOR AUTOMATICALLY DRAWING MAPS AND PLANS FROM TWO TER-RES'IRIAL OR AERIAL PHOTOGRAPHS.

Application filed April 16, 1923, Serial No. 682,417, and in FranceAim-11 25, 1922.

' 15 observed through the same objectives by which they were taken orthrough identical objectives by means of a binocular telescope giving astereoscopic view. Apparatus utilizing this general principle ofobservation is known.

The present invention differs from the known types in the means providedfor the mechanical reproduction of the movements controlling thesighting, and for the markingdof a pointand by the telescope that is useI According to a first embodiment of this invention the observationchambers gare capable of being tilted around a horizontal axis forplacing the apparatus in position, and being swung around a verticalaxis for the observation, which latter is eflected in a fixed verticalplane.

In a second embodiment of this invention 85 observation is made in afixed horizontal plane by tilting the chambers. l In a third embodimentof this invention the chambers are placed in a relative position similarto the relative position occupied 40 by the photographic cameras at thetime of taking the photographs, and they remain stationary'during theobservation.

In a fourth embodiment of this invention a the chambers remain likewisestationary 46 during the observation, and their relative position may bedifierent from the relative 0- sition occupied in space by thephotograpic cameras at the time of takingthe photographs. 7 The present inventionhas the following special advantages 1-, v

(a) The same apparatus allows of producing a. continuous drawing of allthe elementsof the map-- (land surveying, levelling,

contour lines with am lification of the dimensibns) irrespective y ofvthe inclination of the axis of the photographic camera to the vertical(terrestrial photographs, oblique photographs, vertical photographs).

(6) The adjustments for height may be transmitted directly to themovable sighting devices thereby attaining a mechanicalprecision whichis greater than that of the devices for transmitting the othermovements. This fact is of importance in drawing level ling plans wherethe tolerances required for the heights are closer together than for theother co-ordinates.

(0) The sighting errors due to the imperfections in the construction ofthe correcting device of the telescope are reduced to a minimum owing tothe fact that the pointer serving to'represent the optical axis issituated in front of this devlce relative to the path of the rays oflight.

Fig. 1 is a diagrammatic view in perspective illustrating opticalprinciples involved in this invention;

Fig. 2 is a top plan view of the apparatus with certain parts removedfor purposes of clearer illustration;

Fig. 3 is a diagrammatic view illustrating the principles involvedintransferring an; angle 2' nearer to the vertical; I

Fig. 4 is a diagrammatic detail view'illustrating manner of determiningthe angle 0';

Fig. 5 is a top plan view partly in section of the binocular telescope;

Fig. 6 is a top plan detail showing one form of stylus actuating means;

Fig. 7 illustratesin top plan, a recording cylinder and associatedrecording means;

Fig. 8 is a top plan view showing a portion of another embodiment of theinven-- 'tion' I 9-is a horizontal section through-the end of thetelescope shown in Fig. 8;

Fig. 10 is a top planview of mechanism for actuating the telescope inaccordance with a formula hereinafter referred'toi;

Fig. 11 is atop plan view showing anothermechanism for operating thetelescope, and

Fig. 12 is a top plan view showing a third mechanism for operating thetelescope.

Figure 1 illustrates the most general case and in the explanationsrelating thereto of taking the photographs. In this figure -SS'designate the points of View; H is the height of the points of viewrelative to a horizontal plane of comparison. is any iven point inspace. m is its vertical proection upon the plane of comparison, and kis the height of the point M above the said plane. B' is the horizontaldistance between the two points of view S, S taken'parallel to anarbitrary direction X -X. d 3 is the horizontal distance apart, of thepoints S, S, measured on a line at right angles to the said direction. Ij

y y are the distances of the point m from parallel lines drawn through 8and s, the said lines being designated by the letters X-X and X '.X'respectively. at w designate the distances of the points 8 s from theprojection of the point m upon the lines X-X and X'X respectively. a aare the angles enclosed by s m, with X--X and s m with X'X. z z" are theangles enclosed by S M and S M with the vertical. 9, 0 are the anglesdesignating the inclinations, to the vertical, of planes parallel to XX, drawn through the points S-'-M and SM respectively. [i ,8 are theangles formed by S M S M with the direction X X.

Between these various'quantities there cxist the following fundamentalrelations Referring then to Fig. 2 of the drawings, the letter Adesignates one of a pair of chambers, in which the photographs to beobserved are placed, and upon which are mounted the obj ectives O withwhich the photographs were taken or objectives identical therewith.These chambers are each movable around a vertical axis I, and each canreceive a suitable inclination around a horizontal axis ee. They arefixed directly upon the two straight guides R, which carry them in theirrotational motion around I,. They upon a roller carried by a carriage.C, adapt ed to travel along a bridge P parallel to the line I, 1,. Thereare two bridges P and two carriagesC, each imparting rotation to one ofthe chambers. The two bridges Pare Its movement is effected by means ofa handwheel M and a screw V. The movement of the carriage C causes thetwo bridges P to move simultaneously in depth by equal amounts.

The two carriages C, which carry the supporting rollers g, of thestraight guides R, are connected together by a rigid rod t, ofadjustable length (not shown in Figure 2). The assembly of the carriagesC, and the rigid rod t, is entirely similar to the assembly of thecarriages C and the rod t, hereinafter referred to. I

The movement of the two carriages 1S effected by m-rans of a hand-wheelM,, a

groove shaft a, and a screw V, carried by one of the bridges P (notshown in Figure 2).

It will be readily perceived that the sum of the distancesofeach of therollers g, from the straight line passing through the correspondingcentre I, at right angles to the line I, I, will remain constantwhatever may be the position ofthe bridge I and the carriage C,. f I

It care has been taken to make this sum equal to B' (Fig. 1), by actingupon the length of the rod t, and moving the bridges P in depth throughthe distance (l y, then the ang e enclosed by each straight guide 'R,With the line of the centres I, I, is always equal to the angle aenclosed by the line 8 m with the axis X X.

A drawing stylus m, 'iixed to one of the carriages, records on a board Uthe movements of the rollers g,.

The observing telescope is horizontal and parallel to the Line of thecentres I, I,. It

consists of afixed central tube L and twomovable portions l bent offatright angles carrying the objective system. The movable portions Z arecapable of turning independently of each other around the horizontalaxis of the fixed portion L. These two movable portions are sighted in afixed vertical plane at right angles to the axis of the telescope, andthe sighting line meetsv this axis. The horizontala xis of rotation ofthe telescope meets the vertical axis of rotation of the chambers Aapproximately at the forward nodal point of'the objective 0 of thechambers A.

Since the telescope sights in .a fixed vertical plane, the angle ofinclination of the sighting line with the vertical, that is to say, theangle of inclination of the movable portion Z, must be equal to theangle'i of Figure 1 if the chambers are inclined to the vertical to thesame extent as were the photographic cameras at the time of taking thephotographs.

The angle i is obtained and transmitted. to the telescope by reproducingmechanically gether by a rigid rod t of variable length.

Each carriage C carries a roller 9 which causes the rotation of astraight guide R around a fixed axis I situated-on the line I 1 If thedistance of the roller 9 from the perpendicular to the line l: I drawnthrough I is'equa1to (Hh), it will be seen that the angle enclosed bythe straight guide R withthe line I I is the angle 0 defined by therelation I I H'fh. Evhgre 3] is the distance of the roller from If thelength of the rod t is such that the angles marked .bythe two straightguides are equal to the angles 0 of space for a given positiomthey willlikewise be equal for all other positions corresponding to the variousmovementsof the bridge and the group of carriages C The motion of thecarriages C is produced by means of a foot-wheel M a grooved shaft (1and a screw V carried by the bridge P.

On each of these straight guides R there is fixed at 90 thereto astraight guide 73 which moves a roller 9 upon which it rests. Each ofthe straight edges R actuates .a jointed parallelogram composed of twoequal cranks 1' '1" and a link 6 The crank r is fixed to the straightguide R and is rigidly attached at 90 to the latter. The link 22 is atright angles to the line of the centres I I I 1 r y The roller 9 slidesalong the link b Its connection is such that it is always situated at'adistance 1' Sill a from the line at right tan 0= angles to I I drawnthrough the point I (1' begng the common length of the cranks 1' 1 v.Since 9 bears upon 1' as above stated, its distance from the line I Iis equal to rsin root 0. his carried by acarriage G which rolls on astraight gui e r parallel to 1' I 73 is carried by a slideway G at rightangles to: I I and upon which it is able to move in depth by the actionof the straigl t guide r, upon the roller 9 13 carries a roller 9 at oneend; this roller is mounted on a horizontal axis parallel to I I andthis axis meets the axis of the roller 9 The distance of the roller 9from the vertical plane passing through I I is therefore at all timesequal to 1' sin a cot 0.

A straight edge 1' fixed at 90 upon the able known mechanism.

.movable portion of the telescope bears permanently upon this roller 9The axis of the telescope is at a distance r from the horizontal planeswept by the roller 9 The'angle of the straight guide 1' with it'shorizontalplane is therefore theangle a so that cot i=cot 0 sin aThisfltis likewise the angle which is enclosed by the bent-off portion Zof the telescope with the vertical.

The above described'mechanism for transferrin the inclination of thetelescope is applicable only to angles 11 greater than For angles nearerthe vertical the angle z may be reproduced in the same manner accordingto the formula tan 0 tan 'L= sin a (Fig. 3

reproduces the meeting of the link 6 and the slidway 1' and transfersthe length 1' tan d 1' tan 0 The angle 11 is transferred tothe-telescope in a vertical plane by a mechanism. similar to theforegoing transferring mechanism.

R,and whoselinkJb is parallel to X X.

the slideway G which is at- .right angles to X X. I

This length is transferred to the bridge P a by an auxiliary slideway atright angles to X X and capable "of,moving parallel to itself; 1

R; bears then upon the roller g which reproduces the meeting point ofthe slideway and bridge P; it gives theangle'i such that y tan 2 Thisangle is trans ferred into the vertical plane by any s u1t- Thetelescope (Eign- 5) is composed of at fixed portion L and two movableportions Z carrying the objective system. 'The movable portion Zcomprises an optical square 1),, an objective and a pointer f (such as ahair line) situated in the focal plane of 0 The sighting linereconstituted by 0 f is parallel to the axis of rotation; the opticalsquare 72, turns this sighting axis around at right angles to the axisof the telescope.

A system of parallel mirrors 12 p reflects the luminous rays along theaxis of the fixed portion of the telescope. These rays are reeeived ato. by a lens which forms with 0 a non-focal system. They meet at. W acorrecting prism the rotation of which is produced by the differentialmechanism D. The image is observed by means of a telescope l (bent offat 12 having an objective 0 and an eyepiece 0,. The telescope iscomposed of two portions similar to the one above described. Thedistance'between the eyepieces is produced by sliding the telescopes Zalong the axis.

A screw '1) producing the rotation of the fixed ringof the differential,assures a suitable directional position of W. This mocha nism isdesigned to allow of examining phothe chambers.

tographs having any directional air position relatively to the verticalaxis of rotation of In particular it is required for drawing contourlines according to the method hereinafterdescribed.

The actuation of thechambers A andof the movable portions Z of thetelescope may be reversed, that is to say, the angle 0 may be marked onthe straight guide. R and the angle or on the straight guide R Thechambers rotate through the angle 0, and the movable portion of thetelescope rotates through the angle 3 which is defined by the followingequation cot ,8=cot 0: sin 6 5 This angle is the angle formed by theradius S M with the line parallel to X X drawn through the sightingpoints 8. In order to observe under these conditions it is suflicient toturn the photographs through 90 in their lane. This construction isimportant for rawing levelling plans, because since the transference ofthe heights being done directly allows of attaining greater accuracywhich is in agreement with the tolerances prescribed in this case sincethese tolerances are much closer together as regards the heights than asregards the horizontalco-ordinates.v Y A The chambers A may be arrangedin front of or behind the axis I, I and they can be inclined upwardly ordownwardly in relation to the axis I a This arrangement allows ofinspecting positive and negative photographs.

-For drawing survey maps the operator acts upon the handweels M M, M insuch a manner as to bring the movable pointer of the telescope at restin contact with the stereoscopic image of any given curve of the ground.Automatically the Stylus, 112. will draw the projection of this curveupon the board U. l

For contour curves it will be sufficient to fix the carriages C or C, onthe bridges P at a suitable distance from the foot of a perpendiculardrawn from the centres I or I on to these bridges, and 'to move thepointer of the telescope, while retaining per manent contact with theground by acting upon the two handwheels M and M in the case where theheights have been transferred to tlie'carriages C or by acting upon thehandwheels M M in the case where the control of the heights iscitectedby rotating the chambers A. For drawing gradients, the plane ofcomparison is changed by taking the plane of the gradient asthe-horizontal plane, the gradients are drawn in the same manner as thecontour curves in the preceding case. The new heights are the respectivedistances between two points of sight in the plane of the gradient.Since the directional position of the chambers is altered, thestereoscopic effect will be restored by operating the screw '0 of thetelescope differential.

In cases where it is desired to enlarge the dimensions, the selection ofthe direction of the axis X X is no longer arbitrary, and will be ahorizontal line of the first system parallel to the plane of thegradient. The angular difference (I y of the bridges P must thenindicate the difference of the dimension d it between the two points ofview in the normal system. The enlargement will be efl'ected parallellyto the line of the centres by means ofany suitable-known mechanism ofthe lever or toothed wheel type.

For utilizing positive or negative photographs thcre must begiven to thechambers anv inclination in the proper direction upwards or downwards,taking into consideration that the points must pass successively in thedesired order in the vertical plane of observation; an IIIVGI'SIOII ofth1s fixing would lead to a symmetrical drawing of the desired plan. Inorder to allow of greatest possible general application, the chambers Amay be capable of being tilted in forwardly or rearwardly of thetelescope axis; and likewise the direction of the graduation of theheights on the bridge P may be re- I versed at will.

For the purpose of utilizing photographs having a vertical axis thechambers must be tilted in such a manner as to enable the heights tobemarked by means of the; handwheel M. The eo-ordinates of the sightedpoint can be read directly off the bridgc'l.

The marking may be efi'ected in the following manner:

On the bridge P there is fixed an auxiliary device P" (Fig. 6) carryingthe board U which follows the motion of the bridge in emmaits verticalmovements. This auxiliary bridge P carries two carriages C connected tothe carriages C and C ,'and sharing the lateral movements of the latter.On

scale reduced in the ratio of g leaving the two straight guides R atright angles to each other. But by inclining them difierently to thebridge, the map may be'drawn with an enlargement of one of thecoordinates. This device may be employed for drawing gradients.

'The drawing may likewise be made on a recording c linder (Fig. 7). Forthis purpose one o the hand-wheels M or M imparts to a cylinder U (thehorizontal axis of which is parallel to the line of the centres I .1 arotational motion through the medium of any suitable known mechanism.The other hand-wheel produces the motion of a drawing stylus m parallelto the generatrices of the cylinder. This drive may be eflected by meansof a mechanism composed of toothed wheels and screws or by means of amechanism composed of levers, such as the construction shown by way ofexample in Figure 7.

The carriage C carried by the bridge P controls the lateral movement ofa straight guide R carried by a slideway P parallel guide R to rock onacentre 1,.

to I 1,. This straight guide carries an antifriction roller 9 whichcauses a straight his straight guide causes the drawing point m to movealong its slideway P through the medium of an antifriction roller 9 Thecenter I 'is adjustable vertically and lateral.- ly so as to allow ofchanging the scale. In the case of drawing on a board, the drawingstylus m may be removed and replaced by a pantograph which drawsdirectly on a reduced or on an enlarged scale. I

In a second form of construction of the improved apparatus the chambersare caused,

for observation purposes, to tilt around a fixed horizontal axis. Thetele cope is then bent in such a manner that each movable portion l.will rock around a vertical axis. The chambers may assume a suitableinclination on their tilting axis; this' ax'is may be parallel to theaxis of the telescope, or it may be at right angles or oblique thereto.

The angle transmitted to the chamber is one of the angles a or 9. Theangle transmitted to the telescope i the angle i or the angle B.

The angle of the chamber is transmitted by means of a lever mechanismwhich transfers the motion into a vertical plane in the same manner asthe transferring mechanism for the telescope in the precedingconstruction.

A third form of the improved apparatus is shown in- Fi res 8 and 9wherein the observation chain rs are stationary, and fixed in a positionsimilar to the position had by the photographic cameras at the time oftaking the photographs.

The observation chambers A aremovable so as to enable them to bepositioned around two axes at right angles to each other passing throughthe nodal point in front of the objective. They remain fixed during theobservation. f

The telescope is horizontal and compo ed of a fixed central portion Land two movable portions. The fixed portion is identical to that of thetelescope hereinbefore described.

The movable portion always controls the rotation of the corrector W, butthe lenses 0 0 are dispensed with. The mirrors 2, p remaln.

The prism p, is movable around an axis at right angles to the plane ofthe movable portion Z (the plane of the drawing). It

carries on its hypothenuse facet a. small auxiliary prism 12', designedto reflect along the horizontal axis of the bent'portion, the rays oflight coming from a collimator K composed of an objective 0' and anilluminated pointer f situated in the focal plane of 0' The tworeflecting facets of the prisms p and p, are arranged at to each other.By this means the rays of light parallel to the axis of the collimator,issuing from the objective 0 of the chamber, are reflectedirrespectively of the incidence, in the same direction as those comingfrom the point of the pointer f and emerging from the collimator. Therotation of the combination p 12', around the axis at right angles tothe plane of the bent portion Z, is assured by the col-. limator in thefollowing manner :The collimator is capable of rocking around a verticalaxis I and of tilting round a horizontal axis after the fashion of anordinary theodolite. The two axes of rotation intersect each other in'the axis of the telescope approximately in the nodal 'pointin of theobjective 0 of the chamber.

On themovableportion of the telescope front there is mounted a part Kwhich is adapted v "tion of p, p, is assured by any suitable known leveror toothed'wheel mechanism so that. the extent of this rockingshall behalf as small as the rotation of the said part and in'the oppositedirection.

The part K carries a tube which envelops The 1 the collimator. This tubeand the collimator have a common eometrical axis and are able to assumea re ative rotational motion around said axis. The collimator can turnthrou h an angle or around its vertical axis; for t is pur ose itssupport is fixed on the straight gui e R,. Since the straight guide R isfixed, the optical axis of the .collimator is able to sweep through avertical plane enclosing the angle a with the line 1 1 that is to say,with the axis X X as hereinbefore stated. I The movable portion of thetelescope can turn through the angle 0. The axis of the part K is thusable to sweep through the plane passing through the axis of thetelescope and inclined at the an 'le 0 to the vertical.' Now this axiscoincid es with the col-- limator axis. The collimator axis, that is tosay, the direction of the rays of li ht, corresponding to the sightedpoint is It us determined by the intersection of two planes namely avertical lane enclosing an angle 0: With the line X X plane parallel toX X passing through the view point and enclosing an angle 0 with thevertical.

For assuring the rotation of the movable portion Z of the telescope, theangle 0 is transferred in the following manner The straight guide Rwhich reproduces 6 as hereinbefore described carries a straight guide 1'fixed at The straight guide 1', produces by means of an antifrlctionroller 9 the displacement in de th of a carriage c sliding on ahorizonta slideway G .at right angles to I I This carriage C carries anantifriction roller 9 having a horizontal axis. On 9 there rests astraight ide r fixed at 90 on the movable portlon of the telescope. Thedistance of the telescope axis from the horizontal plane swept by theaxis of the roller 9 is ual to the distance'of the centre I from t evertical plane swept by the axis of a roller 9 The remainder of themechanism is similar to that hereinbefore described. The operation ofthe apparatus is the same.

The telescope that is used need not be bent in its movable portion l.The two prisms p 39 are dispensed with. The rotation of the part iseffected then around the axis of the prism system p p' which is drivenby a differential or other mechanism of known type. The common centre ofrotation is then brought in front of the objective 0 and is no longersituated near the nodal ploint. From this there result errors of sigting which may be negligible in certain cases.

The above described apparatus has the drawback of being difiicult ofagplication in the case where the photograp s are inclined at largeangles to thetiltmg axis of the telescope; this is due to the rotationof the entry prisms 2 1) (Fig. 1), and another" In order to avoid thatdrawback the amplitude of the rotation of these prisms p p' may berestrained by a suitable angular displacement of the rotation of thechambers around their vertical axes. In particular they need onlyreceive a tilting motion around the horizontal axis of the telescope;then their optical axis will remain in a fixed vertical plane.

For observation purposes, 31) the collimator K must be suitabl fixecrelatively to the driving straight guic e R (2) The movable ortion ofthe telescope must be set at a suita le angle y.

The fixing of the collimator is easy because the rotational motion ofthe straight guide R is transmitted integrally to it.

In order to obtain the tipping angle of the telescope it is to be notedthat thls angle is given by the trigonometrical relation smcose 11-?where am is the horizontal distance of the sighted point from the viewpoint.

I tan 7;-

I-I-h is the relative height of the'sighted' which the point. e is theangle through collimator is rotated.

We have now\e=E-a where E is the,

angle enclosed in spaceby the plane of the optical axis of the apparatuswith the direction X X and a is the angle of the vertical pointconsidered with sighting plane of the this straight line X -X.

The angle y can be transmitted to the telescope by using any one of thefollowing groups of equations sin e 1 tan 'ytan 0 Sin a cot as 0 sin etan 0 1 2 tan E+tan e cos E tan 'y=tan 0 chanical manner of realizingthe second one of the formulae (1).

The straight guide R controls the simultaneous rotation of two equal andconcen- In Figure 10 is shown a plan of a metrio jointed parallelograms'r b a-" 7'' 6'7, r",, the first being fixed at 90 on-R and the secondbeing fixed at an angle The respective angles of the hand-wheels r',,r", with the. line of the centres I I, are

then 5-0: and e.

The links I), I), move parallel to themselves through a quantity 1' sina 1" cos e.

On the link I), there slides an antifriction roller 9 which moves underthe action of a straight guide "1*, fixed at 90 on the straight guide Rwhichgivesthe angle 0. This roller 9 causes the translation movement ofa straight edge 1*, parallel to I 1,. 0 is carried by a carriage (1movable on a slideway G at right angles to I I second roller 9, connectsb and r Itproduces the rotation of a straight guide 1 mounted loose onthe axle I 'The angle enclosed by this straight guide with thedirection1, I is the complement of the angle y.

In Figure 11 is shown a plan of an ar-v rangement for the mechanicalrealization of the second formulae (cotangents) of the groups'2, 3, 4. Astraight guide 1*, may-be fixed on the straight guide'R the anglebetween these. two straight guides being (90E). The axis of the colima-tor is in the vertical plane of this straight guide. 1",

moves through the medium-of a roller g,, a carriage C,- which is movablelaterally on a slideway G,. This carriage C is con nected to a slidewayb, at right angles to I I, which moves laterally through the sameamount.

A straight guide r fixed at 90 on B moves a roller g, which'bearspermanently upon 9, moves a straight guide 1' carried by a carriage Q;movable on a slideway G paral- 161 to 2),. v

C carries a roller 9,, with horizontal 'axis which serves to transferthe motion into a vertical plane.

Thedistance of the straight line described by the roller g' .fron1 theaxis 1 isequal to r; .or r cot E: or 7' cos E; according as it isdesired to realize any one of the groups 2, 3, 4. The straight guide I),is then fixed at a distance from this roller equal to r tan E; or 1'; or7' sin E.

On the other hand 9 is adjustable as to height on the carriage C and thedistance of the plane .swe t by its axis from the axis of thetelescope18 equal to r cos E; or'rsin E; or according to the case, 3

In the case where it is desired to realize the first ones of theformulae of the group-e 2, 3, 4 (tangents), the -'apparatus shown inFigure 12 may be employed.

The straight guide R moves directly the carriage C 1, bears always upong but'is loose on the axle 1,; :it realizes the angle y which istransferred into the vertical plane by means of a known mechanism bymoving the carriage C carrying the roller 9 The devices for the tangentsare importantin the cases where 0 and the devices for the co-tangentswhen d 45, which is the most general-case, if the auxiliary drawingdevice is employed allowing the chambers to be folded down ashereinbefore described. As. in the preceding case, the actuation for theheights may be transmitted directly to the collimator after-suitablerotation of the pointer and the photographs, and after cor-. rection forbinocular vision by means of the screw V of the telescope.

Having now" particularly described and,

ascertained the nature of my said invention and in what manner the sameis to be performed, I declare that what Iclaim is 1. In an apparatus ofthe character described, a pair of" rotatable observation I chambers,-aperiscopie binocular telescope having rotatable parts provided-withsight- 7 ing marks, and means forsimultaneously actuating theobscrvationchambers and said rotatable telescope parts whereby the steroscopic'mark may be caused to follow the contours of the steroscopic photograph.

2. In an apparatus of-the character de-' scribed, a pair of pivotedchambersfor holding the photographs, a binocular telescope provided withrotated parts, control mechanism for operating said pivoted chambers andtelescope parts, and means interconnecting said mechanism with saidchambers and telescope parts including a system of-guides having fixedcenters, and a plurality "of levers constituting parts of jointedparallelograms and adapted to transfer angular dif ferences due tovariations in height directly to the photographs and telescope.

3. In an apparatus of the character de s'cribed, a pair of pivotedchambers for holding the photographs, a binocular telescope havingrotatable parts, control mechanism for actuating the chambers and meansinterconnecting said mechanism with said cham and chambers. and a styluson said car-' riage adapted to draw the map direct- 1y through themediumof the p'antog'raph. 4. In an apparatus of the character described, apair of pivoted chambers for holding the photographs, a binoculartelescope having rotatable, parts, control mechanism for actuating thechambers and movable telescope parts, means interconnecting saidmechanism with said chambers and rotatable parts including apantographicsystem of guides and levers,-means operatively connected with saidmechanism for drawing gradients, and a seconddrawing means operatively'connected 3 with said mechanism guides inter.- connected by a stylus.

5. In an apparatus oftheIcharacte-r described, mcans for holding thephotographs,

a binocular telescope, means for moving the photograph holding means andparts of said telescope about axes at right angles comprising arectilinearly movable bridge and a pantographic connecting system ofguides, a map holder, stylus holding means,

and means whereby said holding is operativelyconnected with said bridgeand movable parallelto' said map holder.

6. In an apparatus'of' the character described, holding devices for thephotographs movable ona horizontal axis, a binocular telescope forviewing photos in said holding devicesand having objective portionsmovable about a vertical axis and disposed'adjacent thephotographrholding devices, a rectilinearly movable bridge, pantographicconnecting means for moving said bridge, holding devices and movableobjective portions, and a stylus connected with the bridge.

7. In an apparatus of the character described, a pair of photographholders adapted to be set at the sighting angles, a binocular tele copefor viewing photos in said holder having objectives independentlymovabl'e around a common horizontal axis and prisms movable around axesat rlghtangles to-sald horizontal axis, a collimator for moving saidprisms, a system of concentric cardan joints for positioning thecollimator,

, and means for moving said objectives and said collimator, the mainaxes of said joints being movable through the angles 0 and asubstantially as described.

8. In an apparatus of the character described, a pair of photographicholders each adapted to be arranged in any desired position, a binoculartelescope for viewing photos in said holder having objectivesindependently movable around a common horizontal axisand prisms movablearound axes at right angles to said horizontal axis, a collimator formoving said prisms, a system of cardan joints for positioning the sameand including parts rotatable about an axis through the angle or 0and'parts rotatable about an axis through an angle related to the anglea- OI 0 by a predetermined ently movable about the\axis of thetelescope, there being a sighting mark carried by each carriage, andmeans for simultaneously moving the observation chambers and theperiscopic carriages;

10. In a device of thecharacter described,

a pair of pivoted observation chambers, a binocular telescope associatedtherewith, periscopic carriages rotatable about the axis of thetelescope in juxtaposition to the observation chambers, a bridge, acarriage slidable on the bridge, and means whereby the angle ofinclination of the adjustable periscopic carriages maybe transmitteddirectlyto the movable carriage.

11. In a device ofthe character described, a pair of pivoted observationchambers, a binocular telescope associated therewith, periscopiccarriages rotatable around the telescope in juxtaposition to theobservation chambers, a bridge, a carriage slidably mounted on thebridge, and a plurality of rigid lever arms pivotally interconnected,constituting connecting means between the carriage and the periscopiccarriages whereby the angles of inclination of the latter may betransmitted directly to the former.

12. In a device of the character described, a pair of observationchambers each movable about a vertical axis, a telescope associatedtherewith, the longitudinal axis of the telescope intersecting thevertical axes of the observation chambers, periscopic members mounted oneach end of the telescope and adjustable around the axis thereof thefree ends of which are in juxtaposition to the observation chambers, abridge spaced from but parallelto the telescope, carriages slidablymounted on said bridge, and levers for operatively connecting theadjustable periscopic members with the slidable carriages whereby allmotion of the former will-be transmitted directly to the latter.

13. In a device of the character described, a pair of observationchambers each movable about avertical axis, a telescope associatedtherewith, the longitudinal axis of the tele-' scope intersecting thevertical axes of the observation chambers, periscopic sections mountedon each end of the telescope and adapted to be rotated relative to theobservation chambers, a bridge parallel to but spaced fromsaidtelescope, carriages slidably'mounted on the bridge, and a pluralityof angled levers operatively connecting the periscopic sections of thetelescope with said slidable carriages.

' scope intersectin of the bridge sections, a stylus connected to abouta vertical axis, a telescope associated therewith, the longitudinal axisof the telescope'intersecting the vertical axes of the observationchambers, perlscoplc sect1ons mounted on each end of the telescope'andadapted -to be rotated relative to the ob servation chambers,'abridgesparallel vto but spaced from the said telescope, carriagesslidably mounted on the bridge, and a pantograpliic system of leversfor'operatively connecting said carriages with themovable sections onthe telescope.

15. In a device of the character described, a pair of observationchambers each movable about a, vertical axis, a telescope associatedtherewith, the longitudinal axis of the telethe vertical axeseof theobservation cham rs, sections mounted on each end of the telescope andadapted to be rotated relative to the observation chambers, a bridgeparallel to but spaced from the telescope, said bridge beingtransversely divided to form a pair of independent sections, carriagesslidably mounted on each of the bridge sections, and a plurality oflevers:

for o eratively connecting the carriages with t 'e respective movablesections of the telescope. v

16. In a device of the character described, a' pair of observationchambers each movable about a vertical axis, a telescope associatedtherewith, the longitudinal axis of the telescope intersecting thevertical axes of the observation chambers, abridge spaced from butparallel tothe telescope, said bridge be,

transversely divided to form a pair of 1n ependently and rectilinearlymovable sectlons, carriages slidably mounted on each said carriages totrace the movements of the same, anda plurality of levers operatively.

connecting the movable carriages with the respective movable sections ofthe telescolpe whereby all adjustments of the latter re tive to theobservation chambers will be transmitted directly to the movablecarbinocular telescope having" sighting marks rotatable about an axisatright angles to said first named axis, and means for simultaneouslyactuatin said observation chambers and said mova 1e telescope partswhereby the stereoscopic mark may be caused to follow the contours ofthe stereoscopic photograph. I

-18. In apparatus of the character described, a pair of observationchambers ro-- tatable abo t an axis, a binocular telescope having partsrotatable about an axis at right angles to said first named axis,control mechanism for operating said movable chambers and telescopeparts, and means interconnecting said .mechanism, movable chambers andtelescope parts including a system of guides having fixedcenters and aplurality of levers constituting parts of jointed parallelogramsandmdapted to trans lei-angular differences due to variations in heightdirectly to the photographs and telescope. p

19. In apparatus of the character described, a? pair of observationchambers totatable about anaxis, a binocular telescope having partsrotatable about an axis at right angles to said first named axis,control mechamsm for operating said movable chambers and telescopeparts, and means interconnectingsaid mechanism, movable chambers andtelescope parts including a carriage'anda pantographic system of guidesand levers, and a stylus on said carriage adapted to draw the mapdirectly through the medium of the hotographs.

20. apparatus of the character .described, a pair of observationchambers rotatable about an axis, a binocular telesco e having partsrotatable about an axis at rig t angles to said first named axis,control mechand telescopeparts, and means interconnectin said mechanism,movable chambers'a'nd,

te escope parts includinga pantographic system of guides and levers,means operatively connected with said mechanism for drawinggradients,and a second drawin means ope'rativel connected with said mechanismandinclu ing a interconn'fited by a sty us.

i In testimony whereof I afiix' my signature.

, 'GEQRGES JEAN P IVI'LLI Rs air of crossed guides

